GreenLink: An Energy Efficient Scatternet Formation for BLE Devices

Formation technology of Bluetooth scatternet has been researched for over a decade and promoted by rapid development of wearable computing. Limited by technical features, the traditional scatternet formation technology has not been widely used in real commercial chipsets. As new features are introduced into the Bluetooth core field, the ability to use Bluetooth Low Energy (BLE) technology to construct a network becomes the reality and puts forward new challenges. The scatternet formation technology facing to BLE and wearable devices requires significant improvement in energy efficiency. According to our experiments, 92% of the system energy consumption can be attributed to central nodes. In this paper, we presented a Bluetooth scatternet formation technology focused on energy efficiency, GreenLink, which minimizes the amount of central nodes by enhancing system aggregation degree to ensure excellent energy-saving performance. Meanwhile, we implemented a prototype of GreenLink on Nordic nRF51822 chipsets, conducted experiments, and verified in practice. According to the experiments, GreenLink used only 30% central nodes and reduced 50% system energy consumption compared with traditional technology.

Resource Optimization Routing and Scatternet Formation Protocols for Bluetooth Networks

Limited resources and network dynamicity are challenging issues in Bluetooth networks. Therefore, scatternet formation improvement and efficient routing algorithms are required that can efficiently construct a short route between a source and destination. As of today, many protocols have been proposed, mostly researchers focusing on simplicity and reliability, but only few of them fulfill the Bluetooth scatternet scenario. Therefore, it opens new doors for scatternet formation and inter-piconet routing for the Bluetooth scatternet. This paper presents a review of Bluetooth routing and scatternet formation protocols for inter-piconet communication. First, Bluetooth operation is explained followed by important applications and topologies are discussed. Then, inter-piconet routing and network formation protocols are critically analyzed. Finally, Bluetooth problems and open research issues are highlighted.

An Enhanced Protocol for Bluetooth Scatternet Formation and Routing

Formation of scatternet using Bluetooth devices increases device tractability thereby inviting new networking applications to be designed on it. In this paper we propose Bluetooth Scatternet Formation and Routing Protocol (BSFRP). It is a distributed protocol that handles node mobility and enables multi-hop communication. BSFRP defines rules for topology discovery, scatternet formation and routing. The scatternet phase of the protocol works on the principle of leader election. For routing, AODV is modified to address the constraints of scatternets. It improves the AODV route discovery phase by considering hop count, residual node's power, and route lifetime for best route selection. Simulation results show that the scatternet formed by BSFRP has the following properties: the number of piconets formed is close to the universal lower bound, each device on an average does not assume more than 1.15 roles, and the scatternet does not contain any master-slave bridge.

A Mesh Topology Approach for Bluetooth Scatternet Formation

This paper presents the Enhanced Bluetree, a mesh topology scheme for Bluetooth scatternet formation. The scatternet formation algorithm includes two phases. In the first phase, a designated node called the root starts to create a tree-shaped topology and in the second phase the tree-shaped topology is converted into a mesh-shaped topology. In addition, a return connection mechanism is introduced in this phase to generate more connection paths among the nodes. The mechanism contains two scatternet topology models including the slave/slave mesh (SSM) model and the master/slave mesh (MSM) model. The SSM Model builds a mesh-shaped topology by interconnecting more leaf nodes. On the other hand, the MSM Model connects additional intermediate nodes to establish the backbone connection in a mesh-shaped topology. Simulation results show that both the SSM and the MSM of an Enhanced Bluetree more effectively improve the network performance than Bluetree by significantly reducing the average path length.